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Building a Duel Commander deck

For an effective deck building, it is important to know and understand what macrotypes and archetypes are because these concepts allow to analyze the impact of game plans in relation to each other and to anticipate to some extent the strengths and weaknesses of the deck.

Choosing ones game plan

Choosing a game plan comes down to defining the optics of the deck and its angle of attack. Before selecting cards, a few questions need to be asked to set a course. This questioning phase allows to draw the broad lines that define the deck and determine what makes it special:

Alix is looking to build an original deck based on the artifacts. After asking the three questions above, Alix defined the main lines of the desired deck:

This will be a deck with a high density of artifacts and will use Paradox Engine to generate mana. The deck will win the game thanks to the large amount of spells cast in the same turn (the Big Turn) with Aetherflux Reservoir. Also, Alix doesn't know of any decks that have this game plan and therefore thinks it might be worth building.

Optimizing the use of the command zone

The composition of the command zone must have an impact on the construction of the deck. Indeed, the command zone must provide the colors necessary for the fullest expression of the game plan. It must also provide a strategic advantage if possible: it does not seem coherent to play Aminatou, the Fateshifter if no non-land permanent is considered."

The questions must therefore be asked in relation to each other:

In Alix's case, she finds it essential to be able to play Urza, Lord High Artificer, guardians like Demonic Tutor or Enlightened Tutor and pickaxe engines like Jhoira, Weatherlight Captain or Whirlwind of Thought. So there is a need to play at least three to four colors. Among the possible command areas, there are a few notable:

Silas Renn, Seeker Adept

Silas Renn, Seeker Adept

Played with a partner giving access to at least red, Silas Renn would ensure the redundancy of the artefacts. The main weakness of this command zone is the difficult access to a fourth or even a fifth color. If Alix chooses a pair of partners, the deck size will be slightly smaller and the deck may gain in stability.

Golos, Tireless Pilgrim

Golos, Tireless Pilgrim

Golos allows to play all 5 colors while being colorless, which gives more options. If Alix chooses Golos, it'll be possible to add Cascading Cataracts to benefit from the activated ability.

Kenrith, the Returned King

Kenrith, the Returned King

From a Storm perspective, Kenrith allows to use the mana generated to gain a direct advantage. If Alix chooses Kenrith, it will probably be necessary to play Training Grounds to reduce the cost of the activated ability to draw a card.

Choosing the game plan or choose the command zone first?

Choosing the game plan and finding a command zone that then corresponds to it is a process which allows the greatest flexibility and therefore the greatest efficiency once the choice has been made.

Choosing the command zone first and then the game plan will often amount to making sub-optimal choices so that the two correspond. The mismatch between the area of command and the game plan will create friction that will be felt in games that push the deck to its limits.

This is the general case, some strategies are only viable with a particular command zone which alone creates a unique game plan. This is the case with Winota, Joiner of Forces or for example.

Defining the key cards

The key cards are the cards around which the game plan will revolve. This can be creatures for aggressive decks, lands, and ramp for Lands decks, etc.

The objective is to draw a base of about twenty cards which work together and which lay the foundations of the game plan.

Alix decided to build her deck around the following cards:


  • Jhoira, Weatherlight Captain
  • Urza, Lord High Artificer


  • Aetherflux Reservoir
  • Mystic Forge
  • Paradox Engine


  • Tezzeret the Seeker


  • Song of Creation
  • Whirlwind of Thought


  • Enlightened Tutor
  • Intuition
  • Paradoxical Outcome


  • Demonic Tutor
  • Sevinne's Reclamation

Delimit building constraints

Some cards require a suitable construction to be more effective. We must then ask ourselves if the impact of these cards in the game plan is sufficient to play them.

For example, it is possible to play Blood Moon and Tainted Pact in the same deck. However, it is necessary to be able to build taking into account the various constraints.

Here is a list of some cards requiring an adaptation of the choice of cards:

The three stages of deck building

Building an optimal deck requires going through three stages of refinement.

Defining a strategy

It is advisable at this time to complete the deck with the maximum number of cards synergistic with the game plan. Once the deck is completed, a test phase is necessary to determine if the deck plays as expected.

If not, two options are available: stop building the deck or redefine the skeleton and re-embroider around. Move on to the next step if it works.

Defining a tactic

The first phase of testing determined that the deck was worth working on more and it is this phase that corresponds to the longest step: what are the problems facing the deck now? What cards did not work at all when played?

Identifying so-called “useless” cards frees up space in the deck to add solutions to problems encountered during the first phase of testing.

It is then necessary to do intensive and extensive testing as detailed in the next section.

Validating tactics against strategy

Keep in mind that an action does not have to go in the direction of the strategy but must never go in the opposite direction. This step allows to compare the cards chosen in the previous step to their usefulness in the deck.

It is also in this stage that cards out of the game plan are added but which allow the deck to maintain a presence and a high level of threat against the other decks. These are rather defensive cards that are tucked in at this stage of construction.

Avoiding psychological bias

Paulo Vitor Damo Da Rosa mentions in the article <em>8 Biases That Are Making You Worse at Magic</em> published on Channel Fireball involuntary psychological behaviors that alter the perception of data at Magic.

To avoid these biases, here are some questions to ask oneself during the test phases. Keeping a written record of the thoughts also avoids one of the biases listed in the article.

Testing a card

There is no need to wait to draw and play a card to test it. Indeed, the probability of drawing this card in a deck of 98 to 99 cards is low and follows the hypergeometric distribution (to come soon).

It is better to think of the card as being in the command zone and asking oneself the following questions regularly:

Testing and analyzing games

Testing the deck is actually playing games. So these games need to be analyzed to pick what worked and what didn't. This translates into two steps:

  1. Keeping a written record of each part with the following information:
    • Who started?
    • Who mulliganed and how many times?
    • Who won?
    • What is the winrate of the deck?
  2. Studying game's tempo and choices made:
    • What choices have resulted in an advantage in the game and why?
    • Which cards gave an edge and why?
    • Which cards were disappointing in the game and why?
    • Which cards should have been drawn and why?
    • Which cards should not have been drawn and why?

Discussing about ones analysis

Armé de tous ces retours sur chaque partie, il faut comparer son analyse avec son adversaire dans un premier temps puis avec un groupe extérieur à la partie qui permettra de juger si les ressentis à chaud étaient corrects.

The advantage is to consolidate the feedback given on the games and also to compare the methods of analysis to sharpen the gaze and gradually remove the various biases that are thus revealed.

Defining universal acceptance criteria

When building the deck, some effects will have a predefined mana cost that should not be exceed for said effect.

For example, it is accepted that a spot removal costs 2 mana. In the event of additional costs, the advantages provided must be justified and substantial, at the risk of having an ineffective deck.

Likewise, in aggressive decks, it is accepted that a creature must be able to deal as much damage as its mana cost, sometimes more but rarely less.